Impulse transmitter



Oct. 25, 1938. E. SHIPTON ET AL 2,134,626 IMPULSE TRANSMITTER 7 Filed Dec. 12, 1934 5 Sheets-Sheet 1 w. i -nu,

ATTORNEYS Oct. 25, 1938. E. SHIPTON ET AL 2,134,626

IMPULSE TRANSMITTER Filed Dec. 12, 1934 j sheets-she t 2 b c F rr I I q a. 17 12 15 .52

16 H 1? i 20 21 I 5F PM mid H i il ,K--F Z- --71 1 tETJ I P IP j A w W w ft;

/Nl E/V7 ORS r TORNEFS Oct. 25, 1938. E. Sammy ETA]. 2,134,626

IMPULSE TRANSMITTER- Filed Dec. 1.2, 1934 5 Sheets-Sheet s #Zwg ATTORNEYS Oct. 25, 19 38. E. SHIPTON ET AL 2,134,626

IMPULSE TRANSMITTER v I Filed Dec. '12, 1934 7 5 Sheets-Sheet 4 M4, 2% T ATTORNEYS Oct. 25, 1938. E. SHIPTON ET AL IMPULSE TRANSMITTER Filed Dec. 1?, 1934 5 Sheets-Sheet-S j TMNPRS H JKLM ABCD ATTORNEY 5 NVVENTORS Patented Oct. 25, 1938 UNITED STATES IMPULSE TRANSMITTER Edward Shipton, London, and Oscar Douglas Kennedy, Burnham, England Application December 12, 1934, Serial No. 757,245

In Great Britain 8 Claims.

The present invention relates to impulse trans mitters for automatic telephone systems or the like.

The impulse transmitters hitherto employed 5 have generally been of the dial or finger hold type, and have the disadvantage that errors may be easily made in selecting the required number, which results in loss of time in completely redialling the number to be called, and also in expense if the call to the wrong subscriber is completed.

According to the present invention, a calling impulse transmitter for automatic telephone systerms or the like comprises means for setting up the impulses to be transmitted and giving a Visible indication thereof to the calling subscriber. After the number to be called is thus set up and can be seen by .the calling subscriber to be cor- 1 rect, a calling lever, button or the like is operated to send out the calling impulses. The operation of this calling lever or button can restore all the setting up members to zero. Preferably, however, this action does not take place, the setting up members remaining in the same position after the calling lever or button has been oper-- ated. 1

It will thus be seen that with the arrangement according to the invention there can be no possibility of the subscriber accidentally calling the wrong number. Moreover, the arrangement has the advantage that, if the same number has to be called a second time, the setting up means is already set and it is thus only necessary for the calling lever or button to be operated, thus resulting in a saving of time. Further, in several cases it is not necessary to alter all the elements set up and in such cases less operations than are necessary with the ordinary dials need be effected to complete the call. Another advantage of the arrangement is that it is possible to preselect a call; for example whilst still talking on one call a second call may be set up and impulsed out immediately the first call is finished.

According to one embodiment of the invention, the arrangement comprises a number of setting up means corresponding to the number of groups of impulses to be transmitted in effecting a call, for example, when calling with seven groups of impulses, thefirst three setting up devices may represent the first three letters, and the remain ing four setting up devices the four digits of the number to be called. Each setting up device comprises a knob, thumb disc or the like, and, on moving the setting up device, the letter or numeral selected appears in a-corresponding window or aperture in the device. In this way, by

December 12, 1933 looking at the letters and numerals displayed in the various windows, the calling subscriber can see the called number which he has set up. If desired, in addition to or instead of setting up numbers in the windows, the setting up devices maybe provided with pointers moving over a scale on which the numbers or letters are written.

A feature of' the invention consists in constructing the selecting means for the impulse sender so that they may be set in an easy fashion to impulse'accurately the desired number of impulses; This may be effected by providing a spring pressed member adapted to engage in an indentation so as to locate the selecting means in the correct position. Alternatively, the selecting means may be so constructed that accurate setting is not essential, that is to say, so that there will be no fear of incorrect impulses being sent if the setting knobs or the like are not very accurately positioned. A further feature of the invention consists in so constructing the apparatus that the movement of the setting up devices is large compared with the movement 'of the actual selecting means thus still further simplifying accurate setting of the selecting means. i

In the calling systems in use in many automatic telephone areas in which the subscribers numbers include one or more alphabetical num- 3 bers followed by numerical digits, e. g. TEL. 4321, the alphabetical letters are usually arranged in groups of two or three, the same number of impulses being sent out for each letter of a group which is dialled. For instance, in the London area for the letters A, B, C, the same number of impulses, two, is transmitted. Another feature of the invention, therefore, consists in arranging the setting-up devices for the letter impulses so that only one letter is indicated at a time, there being 40 two, three or more positions of the setting-up devices which transmit the same number of impulses. This may be effected by connectingthe setting-up disc or knob with the selecting device by means of epicyclic gearing or by a lost-motion connection. For example, in the case of a thumb disc and associated selecting disc, the connection may bemade by a pin and slot connection so that for several positions of the thumb disc the same position of the selecting disc is obtained. The selecting disc may be sprung into position by means of a locating spring or the like.

A further feature of the invention consists in basing the operation of the apparatus on correct timing. As is well-known the time for transmitting each impulse is one tenth of a second. According to this feature an impulse sender, such as an impulsing cam, is operated continuously after the calling lever or button is operated and the impulsing circuit is completed, short-circuited or a short-circuit is broken at certain times in accordance with the number to be called.

In order that the invention may be more clearly understood, reference will be made to the accompanying drawings, which show by way of example various embodiments of the invention, and in which:

Fig. 1 shows a plan view, partly in section, of one form of the invention.

Fig. 2 shows a section along the line AA in Fig. 1.

Fig. 3 shows a plan view partly in section of a modified form of the arrangement shown in Fig. 1.

Fig. 4 shows a section along the line BB of Fig. 3.

Fig. 5 shows a section along the line 0-0 of Fig. 3 with part of a supporting plate cut away to show the mechanism.

Fig. 6 shows a section through a selecting disc along the line. DD of Fig. 3. i 1

Fig. '7 shows a plan View of another form of the invention.

Fig. 8 shows a side view of a selecting disc as used in the arrangement illustrated in Fig. 7.

Fig. 9 shows a plan view of a modification of the arrangement shown in Fig. 7.

Fig. 10 shows a section along the line EE in Fig. 9.

Referring to Figs. 1 and 2 of the drawings, the device has eight setting-up members, comprising thumb discs 1 to 8 respectively, all rotatably mounted on a shaft 9 carried in the walls it, ii of the casing. The frontperipheries of the thumb discs project through slots l2 in the front wall of the casing, so that they can be adjusted by hand, and each disc carries letters or numerals corresponding to the digits to be called. The actual digit set up at any time is ascertained by viewing it through the viewing window I3.

In the device illustrated, the first thumb disc I is for setting up special calls, such as for dialling 0, or it could be used for making calls in conjunction with a house system. The remaining seven thumb discs are for setting up the seven digits of a seven-digit calling system. In the example shown, the first three digits are letters and the remaining four are numerals.

Connected and rotatable with each of the thumb discs is a selecting disc, numbered M to 25 respectively, and a locating disc, all numbered 22 in the drawings. The selecting disc and its associated locating disc are rigidly connected together. The locating disc has indentations formed around its periphery (see Fig. 2), With which the end of leaf spring 23, rigidly secured to the casing of the mechanism, cooperates to ensure that the selecting discs must be set accurately in position to correctly dial the desired number of impulses. If the selecting disc is not quite accurately set, the pressure of the spring on the side of one of the indentations of the locating disc moves this disc, and thus the selecting disc, into the correct position.

The thumb discs l, 5, 6, l and 8 are rigidly connected to their associated selecting discs and locating discs, but in the case of thumb discs 2, 3 and t which bear the alphabetical letters and in most cases have three letters which give the same number of impulses, the thumb disc is connected to its associated selecting disc by a pin 44 engaging in a slot :35 cut in the selecting disc. The slot is of such a length that whichever of the three letters is showing in the viewing window the selecting disc is moved to such a position that the spring 23 can force the locating disc and thus the selecting disc into the correct position for transmitting the corresponding number of impulses.

. Each selecting disc is made of insulating material and is provided with ten impulses controling members in the form of teeth a, b, c, d, e, f, g, h, i, 7', the first of which corresponds to a time period of one impulse, the second being slightly longer and corresponding to a time period of two impulses, and so on up to 9', which corresponds to a time period of ten impulses. Thus the ten teeth have different dimensions corresponding to the ten numerals 0 to 9 from which each digit of the numbers to be transmitted may be selected. Each selecting disc with its ten impulse controlling members constitutes an impulse controlling device. In addition there is a blank space It on the surface of the wheel, so that if desired this canbe set in position and no impulses at all transmitted, as will be hereinafter explained.

Mounted parallel with the shaft 9 is a spindle 24 which is rotatably supported in the walls Ill and H of the casing and carries the wipers 25 to 32 which cooperate with the impulse controlling devices or selecting discs M to 2! respectively. One end of the shaft 24 passes through the wall H and is connected through gearing to a clockwork driving mechanism 33. The clockwork mechanism may be of any suitable type and is arranged to start and effect one complete revolution of the spindle 24 when the starting handle 34 is depressed. Conveniently, the clockwork mechanism may be of the type in which the driving spring is normally wound, the act of depressing the lever 34 causing the spring to be further .wound and simultaneously to release a retaining catch. On the mechanism rotating the lever 34 is raised by the spring which unwinds by the amount which it had been wound, the retaining stop finally moving in the position to stop the mechanism when one revolution of the spindle 24 has been made. Also geared to the clockwork mechanism is the impulsing cam 35 of known construction which passes between and periodically opens the impulsing contacts 36 to efiect the production of a series of impulses each time the mechanism is operated. The clockwork mechanism drives the impulsing cam at such a speed that an impulse is produced every tenth of a second, and the required total number of impulses are produced during one revolution of the spindle 24. The time taken for a revolution of spindle 24 allows for transmitting ten impulses in respect of each of seven digits plus the minimum interdigital time periods between the consecutive impulsegroups which are necessary to allow the exchange apparatus to function between the transmission of the successive impulse groups.

The wipers 25 to 32 each comprises two spring members bearing contact points which normally engage together. Each of the springs is spaced from its associated spring on the spindle by means of an insulating washer 37, and in order to complete the insulation, the metal spindle 24 is enclosed in a tube of insulating material 38 (see'Fig. 2). The adjacent springs of two different wipers are, however, electrically connected together, that is to say, the right hand spring of wiper 25 is electrically connected to the left hand spring of wiper 26 throughthe metallic spacing collar 39 andso on for the other wipers. The extreme end springs of wipers 25 and 32 are electrically connected to the contacting discs 40, 4| respectively, with which brushes 42, 43 respectively contact. It will be understood from the above that normally the circuit is completed from the brush 42 through the contacting, ring 44, left hand spring of wiper 25 through the wiper contact and right hand spring of wiper 25, metal collar 39, left hand spring of wiper 26 and so on to the contacting ring 4i and the brush 43 so that normally the circuit is completed from brush 42 to 43. By separating any two contact springs of one wiper, however, the circuit is broken, and

- this separating is effected by the insulating selecting disc'in the following manner.

As will be seen from the drawings, the wipers are arranged spirally around the spindle 24 so that only one wiper is in position at a time to engage with a selecting disc. Each wiper is of such a length that it can only engage with the.

tooth of its associated selecting disc and as the wiper shaft and impulse cam are geared together, the length of the tooth positioned to engage with the wiper as shown in Fig. 2 will determine the number of revolutions which the impulsing cam will make whilstthe wiper springs are separated when moving over the tooth and thus the number of impulses transmitted. Care must be taken correctly to shape the tooth and wiper so that the break and make of the circuit is made quickly and decisively, and no undesired impulses are sent. Normally the impulsing contacts 36 are short-circuited through the wiper spindle, that is,

the two contacts of 36 are connected to the brushes 42 and 43 respectively so that unless one set of wiper springs is separated no impulses willbe transmitted. This opening of a'pair of wiper springs by the insulating selecting discs,

however, removes the short-circuit and allows the impulses to be sent over, the telephone line.

The wipers and selecting discs are so designed that even if consecutive wipers engage the longest teeth of the associated selecting discs, there is an interval between the disengagement of one wiper from its tooth and the engagement of the next wiper with its tooth equal to the minimum interdigital period allowable. If wipers engage shorter teeth of the discs the interdigital periods are prolonged.

From the above description it will be understood that each wiper engages in turn with its corresponding selecting disc and will open the circuit along the wiper shaft for a time corresponding to the setting of the selecting discso that the impulses of the number which has been set up are transmitted in correct sequence.

For special calls, such as for calling the operator by dialling 0, the extra thumb disc I is provided which is a special services disc. When this disc is in position ten impulses are sent before any of the other digits set up become operative, thus calling the operator irrespective of the setting of the other thumb disc. Normally, of course, this special services thumb disc would be arranged in such a position that it causes noimpulses to be transmitted, that is, so that no tooth of the selecting disc I4 is arranged in the path of the wiper 25. However, the extra disc is unnecessary as all calls can be made with the normal number of setting-up devices.

In Fig. 2 the'spindle 24 has been shown in a position corresponding to that which it will' assume during rotation. Normally, of course, the wiper 25 will just be above the top of a tooth of its associated selecting wheel so that this wiper is the first one to be operated when the calling lever 34 is depressed.

The speech circuit is normally connected through the wiper arm circuit and impulsing cam contacts'in parallel, both of which are connected in series with the telephone instrument and the exchange line. 1

3-to 5 show a modification of the arrangement shown inFigs. 1 and 2 provide an arrangement in which the mechanism is more compact. As in the arrangement shown in Fig. 1, this modification comprises the thumb discs 2 to B of metal (the thumb disc I and its associated setting-up mechanism are omitted in this modification), which are rotatably mounted on the outer periphery of supporting discs 58 carried on supporting rods 5! mounted between the frames 19 and ll. The supporting discs are spaced from one another by spacing collars 52. The outer peripheries of the supporting discs 5% slide in grooves cut in the thumb discs, the notched portion 53 of the thumb disc, in the case of discs 5, 6, l and 8, closing the groove to keep the supporting discs in position. In the case of thumb discs 2, 3 and 4 the supporting discs are kept in position by a separate ring 54 fastened to the thumb disc, the purpose of which will be more fully explained hereinafter.

To the opposite edge of the thumb discs are attached the toothed selecting discs iii to 2! which have inwardly directed teeth around their inner peripheries. The selecting discs are made of metal and in the particular example have ten teeth the length of the first of Which corresponds too. time period of one impulse, the second corresponds to a time period of two impulses and so on to the last which corresponds to a time period of ten impulses. A blank space is also provided as was the case with the arrangement disclosed in Figs. 1 and 2.

The outer periphery of each of the selecting discs is scalloped to form locating scallops 55. With these scallops a leaf spring 56 cooperates to ensurethat the selecting disc is set accurately in position. a

The centres of the supporting discs 55) are open and allow a spindle 51 to pass therethrough.

This spindle is jo-urnalled in the casing H] and wall H and carries seven pairs of spring wipers 58 to 64 which cooperate with the selecting discs It to 2! respectively. One end of the shaft 51 passes through the wall IE and is connected through gearing to a clockwork driving mechanism 65. The clockwork mechanism may be similar to that described in connection with Fig. 1, the action of depressing the lever 34 serving to wind the clockwork spring arranged in the drum (55. When the lever 34 reaches its fully depressed position it moves a cam 61 to move a spring pressed pawl t8 out of engagement with a notch in the stopping wheel 69 (see Fig. 5). The motor then rotates and the end of the handle 34 moves to release the cam 6'! so that when the spindle 5'! has made one complete rotation the paWlEB again engages with the notch in the stopping wheel [iii to stop the mechanism. Also geared to the clockwork mechanism is the impulsing cam ii! the teeth of which operate a spring set ii to open and close contacts for the transmission of the impulses. The speed of the mechanism may be controlled by the governor 72. The mechanism drives the impulsing cam at a speed to produce an impulse for one tenth of a second or otherwise according to the particular system in which the apparatus is to be used and itis so to the spindle that sufiicient impulses are produced during one revolution of the spindle 5"! to allow for transmitting ten impulses in respect of each group of impulses and to allow for short time intervals between the transmission of two successive impulse groups.

The contacts of each pair of spring wipers 58 to 36 are insulated from one another along the spindle 5? in the same manner as the wipers in Fig. 1. Normally the pairs of springs contact together to short circuit the impulsing circuit but are opened when an insulating member carried by each wiper and shown at Ma and Bla in Figure 3 engages with a tooth of the selecting discs 65 to 2! The arrangement thus works similar to the arrangement described with reference to Figs. 1 and 2.

As in the case of Fig. l the thumb discs 2, 3 and Q bear the alphabetical letters and have three letters which give the same number of impulses. In order to attain this end, the notched discs 530. (which also carry the rings on which the alphabetical l tters are marked) of thumb discs 2, 3 and 4- are rotatably mounted in another groove cut in the outside of the thumb discs 2, 3 and 4 and are given a limited movement by a projection i3 formed in the groove engaging in a slot l4 cut in the notched disc 53a (Fig. 6). This arrangement corresponds to the pin and slot con nection shown in Fig. 1 and the slot is of such a length that whichever of the three letters is showing in the viewing window the selecting disc is moved to such a position that the spring 56 can force the locating discs and thus the select ing disc into the correct position for transmitting the corresponding number of impulses.

Figs. 7 and 8 show another embodiment of the invention. In this arrangement the thumb discs 1 2 to 8 control the operation of sectors 80 over the surfaces of impulse controlling or selecting discs 8| each having ten or more teeth according to the number of impulses to be sent in each group. These teeth are arranged around approximately half the periphery of the selecting disc. All the selecting discs are mounted on the spindle 82 which is journalled in the wall I!) and plate H. The sectors are also approximately semicircular in shape and are carried by sleeves 33 surrounding the shaft 82 so that by moving the thumb disc the sectors may be moved to cut out one or more of the teeth. Rigidly connected to each sector is a locating disc 85 which cooperates with a leaf spring 86 in a manner similar to the spring 23 shown in Fig. 1 to locate the sector in the various positions. Each of the springs 85 is carried from a member rigidly secured to the shaft 82.

Engaging with the periphery of each selecting disc is a set of spring contacts 84 which are vibrated to control the impulsing circuit when moved over the teeth. The spring sets are secured to the casing of the mechanism.

In order to compensate for the three positions corresponding to the same number of impulses for the alphabetical thumb discs 2, 3 and 4 these thumb discs are themselves rotatably mounted on their associated sleeves 83 and connected to the locating discs 85, which are rigidly connected to the sectors, by means of a pin and slot connection as explained above.

The apparatus is driven by a clockwork mechanism 33. On depressing the lever 34 the clockwork mechanism operates substantially as described with reference to Fig. 1. The clockwork mechanism causes the spindle 82 to make seven complete rotations before it is stopped again. Also geared to the clockwork mechanism is a commutator 81 and brush 88 which is geared down 7 to 1, with reference to the shaft 82. This commutator has seven contacts each of which is engaged by the brush 88 for one complete revolution of the shaft 82. The commutator contacts are connected to seven spring sets 84 so that each of the spring sets is connected in sequence in the line circuit and controls the transmission of the impulses in accordance with the setting of its associated selecting disc.

Also geared to the clockwork mechanism is an impulse generating device (not shown), the impulses from which are controlled by the opening and closing of the contacts of the spring sets. When the spindle 82 rotates, the thumb discs, the sectors and the locating discs also rotate, the spring contact sets 84 opening and closing on each rotation and controlling in sequence the impulses sent out in accordance with which spring set is connected to the line circuit through the commutator 81 and the setting of its associated selecting disc.

By making the teeth square out it is possible for the correct number of impulses to be transmited even if the sector is not absolutely accurately positioned, and provided that it reaches to or does not project beyond the tooth in ques tion there will be no fear of incorrect impulses being transmitted.

To effect a call with the apparatus described the. thumb discs are set so that the letters or numbers corresponding to the station to be called appear in the viewing windows. For eX- ample if one of the numbers is 8 the thumb disc is moved around until 8 appears in the viewing window in which position two of the teeth of the corresponding selecting disc are blocked out and eight impulses are sent when the mechanism is operated.

With the apparatus described in Figs. 7 and 8 seven complete turns of the spindle and spring sets are necessary to efiect a call, and in order to reduce the time, the teeth of consecutive selecting discs may be arranged on opposite portions of their peripheries so that the time which would be wasted with the arrangement illustrated in Figs. 7 and 8 in moving the spring sets over the blank portions of the discs until the next set of teeth are engaged is eliminated. In this way the time in making the call is halved and only four complete revolutions of the spindle are necessary.

By arranging the teeth to occupy slightly less than a quarter of the periphery of a disc and using the other quarter to enclose the selecting sector, it is possible to make a single disc do the Work of two, thereby requiring only four spring contact sets for sending seven or eight groups of impulses. The selecting sectors can be arranged adjacent the opposite surfaces of the selecting disc.

The number of selecting discs and spring sets can be further reduced by arranging all the teeth on the periphery of one disc and providing it with all the selecting sectors in which case only one spring set is necessary and the commutator may be entirely dispensed with. Such an arrangement is shown in Figs. 9 and 10 in which (see Fig. 10).

the single impulse selecting disc 90 has its periphery divided up into fourteen sections alternately provided with teeth and plain sections The plain portions are preferably slightly larger than the toothed portions to allow for the interdigital period between the sending of the difierent groups of impulses. Arranged to be moved from a plain portion over its associated adjacent toothed portion are seven selecting sectors 9! to 91 each rotatable about the spindle 98 to which the selecting disc is fixed. Each of the sectors is mounted on a sleeve the first sleeve 99 surrounding the shaft 98, the second sleeve lilfl surrounding the sleeve 99 and so on. The free ends of the sleeves are provided with thumb discs 2 to 8 for setting purposes. Stop-s llll may be provided on the selecting disc for preventing the sectors from being moved over toothed portions with which they are not intended to cooperate.

The sectors are located in position by the locating discs I02 which. cooperate with leaf springs I03 as in the arrangement previously described. To compensate for the three positions for sending the same impulses on the alphabeti-. cal discs 2, 3 and 4 these are connected to the locating discs through'a pin and slot connection.

The spring set H14 is fixed to the spindle I05 of the clockwork mechanism 65, which is substantially the same as that illustrated in Fig. 3 and is arranged to make'one complete rotation when the operating lever 34 is depressed. When the clockwork mechanismis operated the spring set moves around the periphery of the selecting disc and eitherallows the impulses generated by the impulse generator to be transmitted over the exchange line or short-circuits them in accordance withv the setting of the sectors.

Further in all the arrangements described adjusting means may be provided for a final adjustment of the relationship between the selecting discs and the wipers. arrangement shown in Fig. 1 the wiper spindle may have an adjustment relative to the clockwork mechanism or for adjusting the distance between the teeth of the selecting discs and the axis of the wiper spindle.

It will be understood that with the arrangement according to the invention no impulses are sent out over the transmission line to which the device is connected, even though the receiver be lifted, until the calling lever is depressed. Thus it is possible to preselect a call even whilst the exchange line be engaged with an existing call.

By providing a normal position in which no impulses are sent it is possible so to adjust the setting-up members that a part code, such as TOL or TRU may be sent without interference from any other impulse groups. Moreover, it is possibleto transmit impulses from.

any group for testing or other purposes.

Further, by arranging the setting-up devices, such as the thumb discs, so that they can be completely rotated in either direction from any one setting to any other setting, the advantage is obtained that the re-adjusting of the device from one setting to another setting may be made in the minimum of time. For example, if one of the thumb discs indicates figure 9 and the next number to'be called on that disc is 1 it is only necessary to move the disc through three positions, that is through and the normal position to readjust the device to indicate 1 instead of For example, in the having to turn it right back again through eight positions.

The impulsing apparatus according to the invention may be mounted in a separate casing or, alternatively, may be mounted in or on a telephone .instrument in a manner similar to that in which the usual dial is afiixed to the instrument. Further, it might be associated with a preset impulser; that is an impulser which has several complete numbers or series of groups. set up, any one of which may be selected for transmission.

I claim:

. 1. An impulse transmitter for transmitting a plurality of groups of impulses, each group corresponding to a digit of the number to be transmitted, comprising'a plurality of setting-up devices, one for each digit of the number to be transmitted, means for visibly indicating the digit set up by each setting-up device, an impulse generating means adapted to operate continuously each time the mechanism is operated, an impulse controlling device individual to each setting-up device, and means for adjusting the position of each impulse controlling device in accordance with the setting of its associated setting-up device, said impulse controlling devices successively cooperating with the impulse generating means to permit the transmission of groups of impulses corresponding to the digits set-up on the setting-up devices.

2.'An impulse transmitter for transmitting a plurality of groups of impulses, each group cor-' responding to a digit of the number to be transmitted, comprising a plurality of setting-up devices, one for each digit. of the number to be transmitted, means for visibly indicating the number set up, an impulse generating means adapted to operate continuously each time the mechanism is operated, a selecting device individual to each setting-up device, means for adjusting the position of each selecting device in accordance with the setting of its associated setting-up device, a plurality of impulse controlling members on each selecting device having different dimensions corresponding to the different numerals, a plurality of contact devices one for each selecting device and means for moving said contact devices relatively to the selecting devices so that the same cooperate in turn with one impulse controlling member of each selecting device to permit, in association with the impulse generating means, the transmission of each group of impulses and to control the number of impulses transmitted to each group in accordance with the time the contact devices contact with the impulse controlling members.

3. An impulse transmitter for transmitting a plurality of groups of impulses, each group corresponding to a digit of the number ,to be transmitted, comprising impulse generating means adapted to operate continuously each time the mechanism is operated, a plurality of selecting discs one for each group of impulses to be transmitted and each comprising a plurality of impulse controlling members of different lengths corresponding to different time periods, a setting-up device for rotating each selecting disc to bring a particular impulse controlling member into operative position, a plurality of contact devices one for each selecting disc, each contact device being adapted to cooperate with the impulse controlling member that is in the operative position, and means for moving the contact devices relatively to the selecting discs to permit the transmission of each group of impulses and control the number of impulses transmitted in each group in accordance with the time that said contact devices cooperate with the impulse controlling members that are in the operative position.

4. An impulse transmitter for transmitting a plurality of groups of impulses one for each digit of the number to be transmitted, comprising impulse generating means adapted to operate continuously each time the mechanism is operated, a plurality of selecting devices one for each group of impulses, ten impulse controlling members carried by each of said selecting devices, means for adjusting the position of said selecting devices to move any one of the impulse controlling members into the operative position, a rotatable member, a plurality of contact devices carried by said rotatable member, one for each selecting device, and means for rotating said rotatable members with respect to said selecting devices, each contact device being adapted to cooperate with an impulse controlling member on the corresponding selecting device to permit the transmission of each group of impulses and to control the number of impulses transmitted in each group.

5. An impulse transmitter for transmitting a plurality of groups of impulses, each group corresponding to a digit of the number to be transmitted, comprising a plurality of setting up devices, one for each digit of the number to be transmitted, means for visibly indicating the number set up, impulse generating means adapted to operate continuously each time the mechanism is operated, a selecting device individual to each setting-up device, a rotatable spindle, means for rotating said spindle, and a plurality of contact members arranged in spiral staggered relation on said spindle and arranged to cooperate with said selecting devices in turn during a single rotation of said spindle and thereby permit the transmission in sequence of each group of impulses.

6. An impulse transmitter for transmitting a plurality of groups of impulses, each group corresponding to a digit of the number to be transmitted, comprising a plurality of setting-up de vices, one for each digit of the number to be transmitted, means for visibly indicating the number set up, impulse generating means adapted to operate continuously each time the mechanism is operated, a plurality of selecting devices, one for each group of impulses and each comprising an annular disc and impulse controlling members arranged on the internal periphery of said disc, said impulse controlling members being of difierent lengths and corresponding to different time periods, a rotatable spindle arranged within said discs, and a plurality of contact members, one for each impulse group, carried by said spindle and means for rotating the spindle to cause the contact members to cooperate with one of the impulse controlling members on each disc, and thereby permit a group of impulses to be transmitted during a time period corresponding to the impulse controlling member.

7. In an impulse transmitter comprising a plurality of impulse controlling selecting devices, corresponding setting-up devices and means for indicating the number set-up; a lost motion connection between said selecting devices and said corresponding setting-up devices, and locating means associated with each of said selecting devices for holding it in one position whilst the corresponding setting-up device may be moved to any one of several positions.

8. An impulse transmitter comprising a plurality of setting-up devices, means for visibly indicating the number set-up, a series of impulse w controlling selecting devices connected with said setting-up devices, and adapted to be brought into predetermined operative positions, said settingup devices each comprising a rotatable member rotatable through a complete circle which can be rotated in either direction from any one setting to any other setting,

EDWARD SHIPTON.

OSCAR DOUGLAS KENNEDY. 

